Figure 147: Ied, Bay Computer And Ethernet Switch With Self Healing Ring Facilities; Figure 148: Redundant Ethernet Ring Architecture With Ied, Bay Computer And Ethernet Switches; Figure 149: Redundant Ethernet Ring Architecture With Ied, Bay Computer And Ethernet Switches - GE P642 Technical Manual

Chapter 16 - Communications
C264
E01011

Figure 147: IED, bay computer and Ethernet switch with self healing ring facilities

A Self-Healing Management function (SHM) manages the ring.
Under healthy conditions, frames are sent on the main ring (primary fibre) in one direction, with short check frames
being sent every 5 μs in the opposite direction on the back-up ring (secondary fibre).
If the main ring breaks, the SHMs at either side of the break start the network self-healing. On one side of the
break, received messages are no longer sent to the main ring, but are sent to the back-up ring instead. On the
other side of the break, messages received on the back-up ring are sent to the main ring and communications are
re-established. This takes place in less than 1 ms and can be described as "bumpless".
The principle of SHP is outlined in the figures below.
V01013

Figure 148: Redundant Ethernet ring architecture with IED, bay computer and Ethernet switches

V01014
Figure 149: Redundant Ethernet ring architecture with IED, bay computer and Ethernet switches after failure
324
MiCOM
H35
DS Agile Ethernet
IEC 61850 ring network
under normal conditions
Px4x
1 2 3
Switch
Rx (Ep) Tx (Ep)
A B
Tx (Es) Rx (Rs)
Hx5x IED
1 2 3
Switch
Rx (Ep) Tx (Ep)
A B
Tx (Es) Rx (Rs)
Hx5x IED
Px4x
C264
Primary Fibre
1 2 3
Switch
C D
C264 IED
Secondary Fibre
Primary Fibre
1 2 3
Switch
C D
C264 IED
Secondary Fibre
MiCOM
H35
DS Agile Ethernet
IEC 61850 ring network
self healed
Px4x
1 2 3
Switch
E
Hx5x
1 2 3
Switch
E
Hx5x
P64x-TM-EN-1.3
P64x
Px4x